Walmart President and CEO Mike Duke has announced the company's next step on the path to achieving its goal of being supplied 100% by renewable energy.

Unveiled at Walmart's Global Sustainability Milestone Meeting, the company's plan includes two major commitments to achieve by Dec. 31, 2020: driving the production or procurement of 7 GWh of renewable energy globally every year, a 600% increase over 2010 levels; and reducing the kilowatt-hour/square foot energy intensity required to power Walmart's buildings globally by 20% compared to 2010 levels.

Based on external estimates of projected energy costs and other factors, Walmart says the two new commitments will generate more than $1 billion annually in energy savings once fully implemented.

"When I look at the future, energy costs may grow as much as twice as fast as our anticipated store and club growth," Duke said. "Finding cleaner and more affordable energy is important to our everyday low-cost business model, and that makes it important to our customers' pocketbooks. Our leadership in this area is something our customers can feel good about because the result is a cleaner environment. And savings we can pass on to them."